Each year 1.6 million US women undergo biopsy for breast cancer diagnosis. Fortunately fewer and fewer women suffer through open surgical biopsy but rather receive minimally invasive image-guided needle based biopsy. Ultrasound imaging guidance is the dominant modality for this intervention as it offers the greatest balance of safety, patient comfort, expediency, and cost effectiveness. However, for all its safety and convenience, ultrasound imaging quality remains strongly operator dependent. This problem is exacerbated by the fact that ultrasound is optimal for imaging soft tissue and not metallic tools such as needles. What this presents is a new barrier for adoption amongst many would-be practitioners: ultrasound guided needle-based interventions are difficult and require substantial training. ClariTrac Inc. is a startup medical device company that aims to solve this problem. Specifically, ClariTrac is developing a patent pending Modular Ultrasonic Beacon System (MUBS) that consists mainly of a disposable, miniature hardware component to be incorporated with the tip or shaft of needles or other interventional tools. The MUBS is a fully integrated ultrasound transducer with electronics and interconnection. The operating principle of the MUBS is like a beacon: it waits in stand-by to detect ultrasound energy emitted from the ultrasound imaging probe. Upon detecting the probe's energy, the MUBS in turn actively transmits energy back to the probe, in a marco-polo fashion. This returned energy appears as a bright, customizable marker on the ultrasound image that represents the precise location of the interventional tool. We hypothesize this marker will allow the care- provider to perform the procedure with greater ease and precision. Our ultimate goal is to design hardware that serves as a low-cost platform for future innovation in ultrasound enabled interventional tools. These applications extend to nerve block and line-placement, beyond image enhancement to imaging, tissue characterization, monitoring and therapy.